Method of revivifying fuller&#39;s earth and other filtering clays



'- HUGH LOWER-Y,

Patented June 10, 193@ UNI-run, STATES {PATENT orFice OFIAIJ'IONUILLINOIS, assmnon mo STANDARD on. COMPANY, OF WHVITING, INDIANA, A CORPORATION OF mnmna METHOD OF REVIVIFYING FULLER/S mm]; AND o'rnmi FI'LTERING cLAYs,

No Drawing. j

from. The alkali used in commercial operation i s'preferablyisoda ash on acpoimt or cheapness, but other soluble alkalisg such as caustic soda, may be used'if desired. After the alkali treatment the clay may be washed,

dried, andrignited in the usual manner and is found to be substantially as eifective as new clay, The reyivified-clay may,,however, be used in moist condition, for example in the form-0f a pulp and in this case it is unnecessary to dry the clay after washing with aqueous alkaline solution and water as herein described. Such a pulp is suitable for use in contact, filtering processes and particularly in the contactfiltering process described and claimed 'in' patentapplication Serial No. 163,949, filed J anuary 2'1, 1927, by the present applicant and another..' Furthermore, while it is preferred to wash the revivified clay, this step may be omitted, if desired, since in many cases the retention of some alkaline reagent by the dried revived clay or a pulp pf the revived clay, is ul'iobjectionable.

T e method of revivifying the filtering clay is applicable equally to both the fine clays used in contact filtering and to the coarser clays used in perc lation filtering. Iii-using soda ash it is suitable to use a solution of'be- Application filed May 25,

1927. Serial No. 194,257..

ash solution'are pumped off and the clay viiashedwith water) to remove the remaining soda ash. This may-be done by agitating the clay with water while heating to 185 to 210 F. as when treating with soda ash. The washings are repeated until only a trace of soda ash remains in the clay. J Ithas been found that some two or three washings are suflicient.

If necessary, the clay is then dried, ignited j in the usual manner, and ground. It is now substantially as'efi'ective as new clay.

, I During this treatment'the oil content of the clay is lowered from about 35% by weight to about 2% by weight, more or less, so that approximately gallons of oil are IGCOX'GIBL per ton of clay treated. I .The soda'a'sh solution may be brought tostrength. with 'dry' soda and reused in the .treatment of further clay. In operating inthis manner soaps which are .formed, accumu-.

late 1n the sodaash solution andmay be] recovered.

described in connection with the details of a that such details shall be regarded aslimitations upon the scope of theinvention except Although the present invention has beeng' in so far asincluded in the accompanying claims.

I claim:

v 1 The method bf revivifying filtering clay -from mineral oil filtration which consists in washing the clay with-aqueous solution of soda ash while heating to about to 210 I? settling the mixture, removing oil and liquid therefrom, washing the clay with tween 5. and 25? Baum. or higher. 1 V water, and drying and igniting the clay. The following'specific example is given by 2. The method of revivifying oil-laden filway of illustration. Six hundred pounds of used clay are charged to a washing tank and by removing substantial quantities of oil to; 140 gallons of 8 Baum solution of soda g 1 QI'ma BIS therefrom, which ash are added. This q'uantityis sufiicient to cons sts in washing such filter clay with an cover the charge of clay. The mixture is aqueous alkaline solution of an alkaline subagitated with air a'nd'heated with both open stance'of the class consisting of alkali metal and closed'stea'm until the batch reaches about carbonates, and caustic alkalis. to' 210 F. The air and steam are shut 3. The method of revivifying oil-laden off and the mass allowed to stand for about clay used in the treatment of. mineral oils, twelve hours. At the end of this time the which consists in washing the clay with an clayhas settled and the oil and organic matter aqueous alkaline solution of an alkaline subjllQcOIl the surface. The oil and excess soda stance ofthe class consisting of alkali metal 100 terfclay used in the treatment of mineral oils I i carbonates and caustic alkalis, while heating. to about 180- to 210 F. and removing sepasolution of an alkaline substance of the class rated oil and-alkaline solutiontherefrom. v

4. The method of revivifying clay used in the treatment of mineral oils, which consists in heating the clay with an aqueous alkaline consistin V of" alkali metal carbonates, and caustic a alis, allowing the mixture to settle; removing the clay therefrom, and drying and igniting the clay.

In testimony whereof'I have hereunto set my hand this 4th day of May, 1927.

I as 1 HUGH LOWERY. 

